Distribution and residue determination of [ 3H]zearalenone in broilers

[ 3H]Zearalenone was intubated into the crops of 7-week-old broiler chickens, and its distribution was monitored at 0, 0.5, 4, 8, 12, 24, and 48 hr. Metabolic products were measured by gas chromatography-mass spectroscopy and radioimmunoassay. The average recovery of administered radioactivity was 83%. Of the edible tissue, the greatest accumulation of radioactivity occurred in the liver 0.5 hr (0.94%) after administration after which it fell off quickly so that by 48 hr only a trace (0.07%) of radioactivity was found. Muscle, abdominal fat, skin, and heart contained only trace quantities of radioactivity. The bile and gall bladder (4.2%) and excreta (87%) contained the major portion of radioactivity. The excreta was the major avenue of elimination. Total zearalenone and α- and β-zearalenols found in the excreta at 0.5 hr after administration were 0.5 to 3.86 ppm, 8.8 to 2.5 ppm at 4 hr, 12.5 to 121 ppm at 8 hr, 10.1 to 82.7 ppm at 12 hr, 1.6 to 122 ppm at 24 hr, and 39 to 43.5 ppm at 48 hr. The concentration in the muscle ranged from 23 to 25 ppb at 0.5 hr to 4 ppb at 48 hr; the maximum residue found was 111 ppb. The muscle contained only zearalenone and no zearalenol. Zearalenone and α- and β-zearalenols were found in the liver with concentrations ranging between 57 and 1103 ppb when measured by RIA and 17.3 and 2543 ppb when measured by GC-MS. The identity of all metabolites was confirmed by mass spectroscopy. The data suggest little danger from residue in the edible portions. Moreover, analysis of the feces can be used as an indicator of intoxication.